Dodgers lose to the Diamondbacks on a walk-off homer 4-3

First place never felt so fragile.

The Dodgers saw their lead over Colorado in the National League West shrivel to a half-game after dropping a 4-3 decision to Arizona on Tuesday when Diamondbacks outfielder Eduardo Escobar hit a walkoff homer off Kenta Maeda. Escobar led off the inning with a solo shot beyond the right-field fence, erasing any momentum created by a Dodgers rally to tie the score in the top of the inning.

As Maeda departed the building without speaking to reporters, the Dodgers pondered their missed opportunities and the consequences of them. Despite a pair of tying rallies against Arizona’s bullpen, the team still went two for 12 with runners in scoring position and stranded nine runners.

“There were three opportunities with a guy at second base with nobody out,” manager Dave Roberts said. “And to not be able to get that guy to third base, I think was the difference in the game.”

The last missed chance occurred in the ninth. Enrique Hernandez sparked the rally with a leadoff single. He stole second base and took third on an errant throw by Arizona catcher Chris Stewart. Chris Taylor tied the score with a ground-rule double. But Joc Pederson, Justin Turner and Max Muncy could not bring Taylor home, and Maeda failed to record an out in the bottom of the inning.

As the Dodgers (88-70) stumbled, the Rockies continued to roll. They blitzed Philadelphia for the second night in a row and extended their winning streak to five. Even if the Dodgers win Wednesday’s series finale, Colorado could still secure a tie if they win again Wednesday, then Thursday when the Dodgers have the day off.

“Obviously, it’s a different ballgame,” Roberts said. “We’re a half-game up. Even in the loss column [actually they’re tied with the Rockies at 70 losses]. But we still got to go out there and win baseball games.”

Walker Buehler gave up two runs in the sixth inning, his final one on the day. He breezed through the first five frames before bumping into trouble. Buehler gave up four hits and struck out six.

Cody Bellinger provided the first run for his team with a solo home run. Yasmani Grandal delivered his second triple of the season to help tie it in the seventh — before Dylan Floro unraveled in the bottom of the inning.

The Dodgers struck first. They were facing Matt Koch, a 27-year-old rookie right-hander, who was supposed to serve as a respite between seeing Robbie Ray on Monday and Zack Greinke on Wednesday.

Bellinger punished Koch for a cutter at the waist, launchig his 24th homer of the season, a second-inning solo shot.

In four starts earlier this month, Buehler fanned 37 batters in 261/3 innings. He aimed for efficiency Tuesday.

He struck out only one batter during the first two frames but collected six outs in 20 pitches. The third inning was less brisk: He needed 18 pitches to complete the frame.

Buehler buzzed through the heart of Arizona’s batting order in the fourth. He enticed shortstop Ketel Marte to pound a first-pitch curveball into the ground for an out. He finished off outfielder David Peralta with an 87-mph cutter for a strikeout. Buehler ended the inning by fooling first baseman Paul Goldschmidt with a slider and collecting his fourth strikeout of the evening.

Buehler expedited Koch’s departure from the game in the fifth, recording the first walk of his career to begin the inning. Koch exited a batter later, after Pederson hit into a fielder’s choice. Into the game came reliever Jimmie Sherfy, who got Turner to ground out before striking out Muncy to end the inning.

“We had our chances,” Roberts said.

The Dodgers had traffic on the bases in each of the first five innings. The threats were extinguished in disheartening fashion. Manny Machado hit into a double play with two runners aboard in the third. Yasiel Puig bounced into a double play moments after Bellinger led off the fourth with a single.

Buehler utilized a similar strategy in the bottom of the fifth. He yielded a one-out single to outfielder A.J. Pollock. It was only the second hit for Arizona. Buehler then got Chris Owings to roll into an inning-ending double play.

On a third turn through the batting order, the Diamondbacks taxed Buehler. After two quick outs in the sixth, Buehler gave up a single to leadoff hitter Jon Jay. Marte followed with a walk. Peralta put Arizona on the board by smashing a 97-mph fastball into the right-center gap for a two-run double.

The Dodgers did not wait long to answer.

Grandal opened the seventh inning by cranking a 94-mph fastball from Arizona reliever Silvino Brancho off the wall in center field. The ball caromed off the wall and across the grass as Grandal lugged himself to third base. Hernandez tied the score soon after with a single.

“I pretty much just made them pay every time they made a mistake,” Grandal said.

In the bottom of the seventh, Roberts attempted to mix and match his pitchers, using Scott Alexander for one out in the inning before turning to Floro. After loading the bases, Floro was unable to put away Ildemaro Vargas, a rookie hitter batting .077.

Floro was supposed to face Pollock and Owings. He failed against both. Pollock singled. Owings smacked a double. A late stop sign from Arizona third-base coach Tony Perezchica kept Pollock from scoring. After Floro intentionally walked Escobar, who was entering the game as a pinch-hitter, Vargas came to the plate.

Vargas can hit from either side of the plate — in theory. He was one for 13 in 2018 before facing Floro. Vargas ripped a single into center field to bring Pollock home and put Arizona back in front.

The Dodgers tied the score in ninth before Maeda gave up the winner. The defeat tightened the race. The players greeted the result with a shrug.

“We win more than we lose, we’ll probably make the playoffs,” Buehler said. “We’ve got four games. If we win three of them, we’ll probably be in.”

andy.mccullough@latimes.com

Twitter: @McCulloughTimes